This invention relates to a method for dispersing comminuted solids. In a particular aspect, this invention relates to dispersing solids in an aqueous medium.
Slurries and suspensions of comminuted solids in an aqueous medium are customarily formed using a dispersing agent. Such an agent can be inorganic, such as alkali phosphates, or more often an organic surfactant is used. Such surfactants include fatty acid soaps of an alkali metal or an alkanolamine, a long chain quaternary ammonium halide, or a non-ionic, such as a polyoxyethylene ether or ester. Also, alkanolamines per se have been used to disperse powdered titanium dioxide to produce slurries which are used in a variety of ways, such as to provide a convenient form for shipping the pigments, or for the preparation of water-based coating materials. As another example, it is known from U.S. Pat. Nos. 3,702,773 and 3,772,046 and Canadian Patent 776,183 to prepare aqueous slurries of titanium dioxide using an alkanolamine, such as 2-amino-2-methyl-1-propanol (hereinafter designated AMP).